The Iowa Pleistocene snail, also known as the Pleistocene disk, scientific name Discus macclintocki, is a very small air-breathing land snail, a terrestrial pulmonate gastropod mollusk.
This snail now occurs nowhere else in the world but a few specialized locations: 37 algific talus slopes in Iowa and Illinois. Algific talus slopes are areas of talus or scree that are "cold-producing", in other words they are part of a natural air-exchange system that renders the microclimate there colder than it is in the immediately surrounding areas. This is a relict species from the ice age and cannot survive in warmer areas.
The Iowa Pleistocene snail is an endangered species, in danger of becoming extinct.
Read more about Discus Macclintocki: Habitat, Size, Causes of Endangered Status, Protection